RequestParameter (Tapestry API - 5.7.0)

```
@Target(PARAMETER)
@Retention(RUNTIME)
@Documented
@UseWith({COMPONENT,MIXIN,PAGE})
public @interface RequestParameter
```
Annotation that may be placed on parameters of event handler methods. Annotated parameters will be extracted from the request, then converted to the type of the parameter. Such parameters are separate from ordinary context parameters (extracted from the Request path). Typically, this is used when client-side JavaScript adds a query parameter to a request to communicate some information from the client side to the server side. Individual fields may also be directly mapped to query parameters using the ActivationRequestParameter annotation.

Since:

5.2.0

See Also:

OnEventWorker

Required Element Summary

Required Elements
Modifier and Type Required Element Description

String value
The name of the query parameter to extract from the request.

Optional Element Summary

Optional Elements
Modifier and Type	Optional Element	Description
`boolean`	`allowBlank`	If false (the default), then an exception is thrown when the query parameter is read, if it is blank (null or an empty string).

- Element Detail
  - value
```
String value
```
    The name of the query parameter to extract from the request.
- - allowBlank
```
boolean allowBlank
```
    If false (the default), then an exception is thrown when the query parameter is read, if it is blank (null or an empty string). If true, then blank values are allowed and will be passed through the appropriate ValueEncoder implementation.
    
    Default:
    
    false